<?php

/* Version 0.9, 6th April 2003 - Simon Willison ( http://simon.incutio.com/ )
   Manual: http://scripts.incutio.com/httpclient/
*/

class HttpClient
{
	// Request vars
	var $host;
	var $port;
	var $path;
	var $method;
	var $postdata = '';
	var $cookies = array();
	var $referer;
	var $accept = 'text/xml,application/xml,application/xhtml+xml,text/html,text/plain,image/png,image/jpeg,image/gif,*/*';
	var $accept_encoding = 'gzip';
	var $accept_language = 'en-us';
	var $user_agent = 'Incutio HttpClient v0.9';
	// Options
	var $timeout = 20;
	var $use_gzip = false;
	var $persist_cookies = true;  // If true, received cookies are placed in the $this->cookies array ready for the next request
							// Note: This currently ignores the cookie path (and time) completely. Time is not important, 
							//       but path could possibly lead to security problems.
	var $persist_referers = true; // For each request, sends path of last request as referer
	var $debug = false;
	var $handle_redirects = true; // Auaomtically redirect if Location or URI header is found
	var $max_redirects = 5;
	var $headers_only = false;    // If true, stops receiving once headers have been read.
							// Basic authorization variables
	var $username;
	var $password;
	// Response vars
	var $status;
	var $headers = array();
	var $content = '';
	var $errormsg;
	// Tracker variables
	var $redirect_count = 0;
	var $cookie_host = '';
	
	function HttpClient($host, $port=80)
	{
		$this->host = $host;
		$this->port = $port;
	}
	
	function get($path, $data = false)
	{
		$this->path = $path;
		$this->method = 'GET';
		
		if ($data) {
			$this->path .= '?'.$this->buildQueryString($data);
		}
		
		return $this->doRequest();
	}
	
	function post($path, $data)
	{
		$this->path = $path;
		$this->method = 'POST';
		$this->postdata = $this->buildQueryString($data);
		return $this->doRequest();
	}
	
	function buildQueryString($data) {
		$querystring = '';
		
		if (is_array($data)) {
			// Change data in to postable data
			foreach ($data as $key => $val) {
				if (is_array($val)) {
					foreach ($val as $val2) {
						$querystring .= urlencode($key).'='.urlencode($val2).'&';
					}
				} else {
					$querystring .= urlencode($key).'='.urlencode($val).'&';
				}
			}
			$querystring = substr($querystring, 0, -1); // Eliminate unnecessary &
		} else {
			$querystring = $data;
		}
		
		return $querystring;
	}
	
	function doRequest()
	{
		// Performs the actual HTTP request, returning true or false depending on outcome
		if (!$fp = @fsockopen($this->host, $this->port, $errno, $errstr, $this->timeout)) {
			// Set error message
			switch($errno) {
				case -3:
				$this->errormsg = 'Socket creation failed (-3)';
				case -4:
				$this->errormsg = 'DNS lookup failure (-4)';
				case -5:
				$this->errormsg = 'Connection refused or timed out (-5)';
				default:
				$this->errormsg = 'Connection failed ('.$errno.')';
				$this->errormsg .= ' '.$errstr;
				$this->debug($this->errormsg);
			}
			return false;
		}
		
		socket_set_timeout($fp, $this->timeout);
		$request = $this->buildRequest();
		$this->debug('Request', $request);
		fwrite($fp, $request);
		
		// Reset all the variables that should not persist between requests
		$this->headers = array();
		$this->content = '';
		$this->errormsg = '';
		
		// Set a couple of flags
		$inHeaders = true;
		$atStart = true;
		
		// Now start reading back the response
		while (!feof($fp))
		{
			$line = fgets($fp, 4096);
			
			if ($atStart)
			{
				// Deal with first line of returned data
				$atStart = false;
				if (!preg_match('/HTTP\/(\\d\\.\\d)\\s*(\\d+)\\s*(.*)/', $line, $m)) {
					$this->errormsg = "Status code line invalid: ".htmlentities($line);
					$this->debug($this->errormsg);
					return false;
				}
				$http_version = $m[1]; // not used
				$this->status = $m[2];
				$status_string = $m[3]; // not used
				$this->debug(trim($line));
				continue;
			}
			
			if ($inHeaders) {
				if (trim($line) == '') {
					$inHeaders = false;
					$this->debug('Received Headers', $this->headers);
					if ($this->headers_only) {
						break; // Skip the rest of the input
					}
					continue;
				}
				
				if (!preg_match('/([^:]+):\\s*(.*)/', $line, $m)) {
					// Skip to the next header
					continue;
				}
				$key = strtolower(trim($m[1]));
				$val = trim($m[2]);
				// Deal with the possibility of multiple headers of same name
				if (isset($this->headers[$key])) {
					if (is_array($this->headers[$key])) {
						$this->headers[$key][] = $val;
					} else {
						$this->headers[$key] = array($this->headers[$key], $val);
					}
				} else {
					$this->headers[$key] = $val;
				}
				continue;
			}
			
			// We're not in the headers, so append the line to the contents
			$this->content .= $line;
		}
		
		fclose($fp);
		
		// If data is compressed, uncompress it
		if (isset($this->headers['content-encoding']) && $this->headers['content-encoding'] == 'gzip')
		{
			$this->debug('Content is gzip encoded, unzipping it');
			$this->content = substr($this->content, 10); // See http://www.php.net/manual/en/function.gzencode.php
			$this->content = gzinflate($this->content);
		}
		
		// If $persist_cookies, deal with any cookies
		if ($this->persist_cookies && isset($this->headers['set-cookie']) && $this->host == $this->cookie_host)
		{
			$cookies = $this->headers['set-cookie'];
			if (!is_array($cookies)) {
				$cookies = array($cookies);
			}
			
			foreach ($cookies as $cookie)
			{
				if (preg_match('/([^=]+)=([^;]+);/', $cookie, $m)) {
					$this->cookies[$m[1]] = $m[2];
				}
			}
			
			// Record domain of cookies for security reasons
			$this->cookie_host = $this->host;
		}
		
		// If $persist_referers, set the referer ready for the next request
		if ($this->persist_referers) {
			$this->debug('Persisting referer: '.$this->getRequestURL());
			$this->referer = $this->getRequestURL();
		}
		
		// Finally, if handle_redirects and a redirect is sent, do that
		if ($this->handle_redirects)
		{
			if (++$this->redirect_count >= $this->max_redirects)
			{
				$this->errormsg = 'Number of redirects exceeded maximum ('.$this->max_redirects.')';
				$this->debug($this->errormsg);
				$this->redirect_count = 0;
				return false;
			}
			
			$location = isset($this->headers['location']) ? $this->headers['location'] : '';
			$uri = isset($this->headers['uri']) ? $this->headers['uri'] : '';
			if ($location || $uri) {
				$url = parse_url($location.$uri);
				// This will FAIL if redirect is to a different site
				return $this->get($url['path']);
			}
		}
		return true;
	}
	
	function buildRequest()
	{
		$headers = array();
		$headers[] = "{$this->method} {$this->path} HTTP/1.0"; // Using 1.1 leads to all manner of problems, such as "chunked" encoding
		$headers[] = "Host: {$this->host}";
		$headers[] = "User-Agent: {$this->user_agent}";
		$headers[] = "Accept: {$this->accept}";
		
		if ($this->use_gzip) {
			$headers[] = "Accept-encoding: {$this->accept_encoding}";
		}
		$headers[] = "Accept-language: {$this->accept_language}";
		
		if ($this->referer) {
			$headers[] = "Referer: {$this->referer}";
		}
		
		// Cookies
		if ($this->cookies) {
			$cookie = 'Cookie: ';
			foreach ($this->cookies as $key => $value) {
				$cookie .= "$key=$value; ";
			}
			$headers[] = $cookie;
		}
		
		// Basic authentication
		if ($this->username && $this->password) {
			$headers[] = 'Authorization: BASIC '.base64_encode($this->username.':'.$this->password);
		}
		
		// If this is a POST, set the content type and length
		if ($this->postdata) {
			$headers[] = 'Content-Type: application/x-www-form-urlencoded';
			$headers[] = 'Content-Length: '.strlen($this->postdata);
		}
		
		$request = implode("\r\n", $headers)."\r\n\r\n".$this->postdata;
		return $request;
	}
	
	function getStatus()
	{
		return $this->status;
	}
	
	function getContent()
	{
		return $this->content;
	}
	
	function getHeaders(){
		return $this->headers;
	}
	
	function getHeader($header)
	{
		$header = strtolower($header);
		if (isset($this->headers[$header])) {
			return $this->headers[$header];
		} else {
			return false;
		}
	}
	
	function getError()
	{
		return $this->errormsg;
	}
	
	function getCookies()
	{
		return $this->cookies;
	}
	
	function getRequestURL()
	{
		$url = 'http://'.$this->host;
		if ($this->port != 80) {
			$url .= ':'.$this->port;
		}            
		$url .= $this->path;
		return $url;
	}
	
	// Setter methods
	function setUserAgent($string)
	{
		$this->user_agent = $string;
	}
	
	function setAuthorization($username, $password)
	{
		$this->username = $username;
		$this->password = $password;
	}
	
	function setCookies($array)
	{
		$this->cookies = $array;
	}
	
	// Option setting methods
	function useGzip($boolean)
	{
		$this->use_gzip = $boolean;
	}
	
	function setPersistCookies($boolean)
	{
		$this->persist_cookies = $boolean;
	}
	
	function setPersistReferers($boolean)
	{
		$this->persist_referers = $boolean;
	}
	
	function setHandleRedirects($boolean)
	{
		$this->handle_redirects = $boolean;
	}
	
	function setMaxRedirects($num)
	{
		$this->max_redirects = $num;
	}
	
	function setHeadersOnly($boolean)
	{
		$this->headers_only = $boolean;
	}
	
	function setDebug($boolean)
	{
		$this->debug = $boolean;
	}
	
	// "Quick" static methods
	function quickGet($url)
	{
		$bits = parse_url($url);
		$host = $bits['host'];
		$port = isset($bits['port']) ? $bits['port'] : 80;
		$path = isset($bits['path']) ? $bits['path'] : '/';
		
		if (isset($bits['query'])) {
			$path .= '?'.$bits['query'];
		}
		$client = new HttpClient($host, $port);
		
		if (!$client->get($path)) {
			return false;
		} else {
			return $client->getContent();
		}
	}
	
	function quickPost($url, $data)
	{
		$bits = parse_url($url);
		$host = $bits['host'];
		$port = isset($bits['port']) ? $bits['port'] : 80;
		$path = isset($bits['path']) ? $bits['path'] : '/';
		$client = new HttpClient($host, $port);
		
		if (!$client->post($path, $data)) {
			return false;
		} else {
			return $client->getContent();
		}
	}
	
	function debug($msg, $object = false)
	{
		if ($this->debug) {
			print '<div style="border: 1px solid red; padding: 0.5em; margin: 0.5em;"><strong>HttpClient Debug:</strong> '.$msg;
		if ($object) {
			ob_start();
			print_r($object);
			$content = htmlentities(ob_get_contents());
			ob_end_clean();
			print '<pre>'.$content.'</pre>';
		}
			print '</div>';
		}
	}  
}

?>